eye-move.js

var box, boxCenter;

$(document).ready(function() {
	
	box=$(".box");
	boxCenter=[box.offset().left+box.width()/2, box.offset().top+box.height()/2];

})

$(document).mousemove(function(e){    
            
	var angle = Math.atan2(e.pageX- boxCenter[0],- (e.pageY- boxCenter[1]) )*(180/Math.PI);	    
    
    box.css({ "-webkit-transform": 'rotate(' + angle + 'deg)'});    
    box.css({ '-moz-transform': 'rotate(' + angle + 'deg)'});
    box.css({ 'transform': 'rotate(' + angle + 'deg)'});
    
});